This invention relates to a structure of changeable shape. Such structures may be of application in many different fields, for example, but not limited to, toys, puppets, sculptures, prosthetic equipment, animatronics, robots or dolls.
In a particular embodiment, such a structure may find application in the field of stop motion animation, and for the sake of example only, it is this application which will be described in more detail herein.
Stop motion animation is a well-known form of animation in which in order to create the illusion of movement of a figure, the figure is photographed in a time sequence, where the figure is incrementally moved between each photograph. It is therefore necessary to use a figure which is capable both of small, incremental movements, and which can remain in a set position once so moved.
Conventionally, such a figure comprises a number of elements. For a human body figure for example, the body may include an articulated skeleton, which defines and limits the major body movements possible, e.g. raising an arm, bending a knee, while preventing impossible or unlikely movements, e.g. flexing the middle of a thighbone. Set around the skeleton will be a body form which defines the volumetric shape of the figure. This will typically comprise a bulky yet flexible material, such as sponge, foam rubber, Plasticine®, clay or the like. This can be carved or set to form the required body shape. Sometimes, around the body form is a body covering (i.e. “skin”), which is flexible to allow movement of the figure. Typically, silicone or rubber may be used for this purpose. In addition, the covering layer may be provided with relief features, so that features of the figure may be accentuated.
There are various problems associated with such known figures. For example, a large volume of material (foam, plasticine etc) is required for the body form. In addition, when the figure is manipulated, the foam material is prone to loss of volume, creasing or rippling, which detracts from the realism of the figure. Furthermore, such figures typically suffer from a relatively poor range of movement of certain body features, for example a figure's neck, limbs, mouth and eyebrows.